A toner cartridge used in an image forming device, such as a copying machine, a facsimile machine, and a printer, generally comprises a rotary provided with a plate shaped agitator that agitates a toner, a rotary provided with a transporter for transporting the toner, and the like.
When these rotaries are fixed to the toner cartridge, a shaft tip on the drive side of the rotary, which is the left side end depicted in FIG. 1, is supported by a pivot at the outer side of the toner cartridge, and the other shaft tip, which is the right side end depicted in FIG. 1, is supported by insertion into a pocket shaped bearing formed inside the toner cartridge in a surface opposite the pivot. Furthermore, the rotary generally comprises a flexible member, such as a soft resin, and the mounting of the rotary inside the toner cartridge is performed by inserting the shaft tip of the rotary into the bearing while flexing the rotary.
Nevertheless, there is a risk that the shaft tip of the rotary will completely detach from the bearing on the non-drive side when an external force, such as a shock caused by a drop, acts to flex the rotary, because the rotary of a conventional device comprises a flexible member and its mounting to the toner cartridge is constituted by simply inserting the shaft tip of the rotary into the bearing. In particular, if the rotary is provided with a plate shaped agitator, then the rotary is easily flexed by the pressing of the weight of the toner upon the agitator, which is a problem because the shaft tip of the rotary can easily detach from the bearing. In addition, in the case of a large capacity toner cartridge, the rotary is long in the axial direction, which increases the play in the bearing on the non-drive side, and, consequently, the shaft tip of the rotary easily detaches from the bearing.
The present invention was created with consideration of such problems, and it is an object of the present invention to provide a toner cartridge that has a simple constitution and a low cost, and wherein the shaft tip of the rotary does not detach from the bearing even if an external force is exerted.